1. Field of the Invention
The present invention relates to a short probe electrical contactor apparatus. More particularly, the present invention relates to an electrical interconnect system for efficient and effective automated or manual testing of integrated circuit devices.
2. Description of Related Art
Many different apparatus exist for establishing connections between two electrical conductors. With the widespread use of integrated circuit ("IC") devices in today's technology, many manufacturers have developed various apparatus to effectuate connections between IC devices and, for example, motherboards and load boards. Such boards have conductive paths that permit interconnection of multiple IC devices, as well as interconnection of IC devices to other types of electrical devices, such as capacitors, resistors, transformers, etc.
With the advent of IC devices, it was necessary to test such devices to determine whether they perform as expected before injecting them into the market for sale and/or use. As a result, an industry arose to facilitate and optimize IC device testing. This industry developed various apparatus that establish interconnections between an IC device and a load board, in order to test the device.
Conventional IC device testing apparatus incorporated relatively long conductive "probes" that establish the connection between the device and the load board. Longer probes, however, create undesirable electrical characteristics, such as increased resistance. Accordingly, in order to optimize the connection between the IC device and the load board, it is important to minimize the distance that current must travel through the probe.
Testing apparatus manufacturers have developed short probe "contactor socket" that reduce probe length and thus improve the interconnection between the IC device and the load board. Such contactor sockets include numerous z- or s-shaped probes seated in slots in a housing. At least two elastomer (or rigid) bands are supplied that run along the slots, securing the probes within the slots and allowing the probes to move in response to engagement with an IC device.
Conventional short probe contactor sockets, however, have several deficiencies. First, they promote a "wiping action" of the probes along the traces on the load board, thereby damaging those traces with each successive testing iteration. Second, they require at least two elastomer bands to secure the probes within the slot. Third, they require removal of all of the probes to allow replacement of the bands when they wear-out. And because the bands wear-out much more quickly than do the probes and the probes are quite difficult to remove, replacement of the bands is time-consuming and costly. Fourth, conventional short probe contactor sockets, due to their design, provide only limited upward force against the leads of the IC device, resulting in poor or ineffective connections in some instances.
An additional limitation in conventional short probe contactor sockets involves alignment of the IC device within the contactor. Conventional contactor sockets provide means (usually posts) to align the IC device, such posts being molded into the cover. Location of the posts on the cover, however, causes two sources of error in obtaining proper alignment of the IC device within the contactor socket. The first source of error results from the tolerances between the posts and the probes, inevitably leading to some misalignment between the leads of the IC device and the probes. The second source of error stems from the posts being located on the cover, which must be attached and aligned to the housing. Because the posts are on the cover, any misalignment of the cover with respect to the housing will lead to further misalignment of the IC device leads with respect to the probes.
Many contactor sockets can be used manually (i.e., hand testing) or in conjunction with a machine (i.e., automated testing). In automated testing, a "mechanical nest" picks-up the IC device by means of a vacuum and delivers the IC device into the contactor socket. In hand testing, by contrast, the IC device is manually inserted into the contactor socket, and a "manual nest" is placed inserted into the contactor socket, in the process pressing down the IC device so that it makes full contact with the probes in the contactor socket.
In conventional contactor sockets, however, the manual nest is semi-permanently affixed to the socket by means of a hinge and a latch, making removal of the manual nest time-consuming. When a user wants to switch from manual to automated testing or vice versa, he or she must detach or attach the hinge of the manual nest from the socket. This requires removal or insertion of screws and bolts that maintain the hinge on the socket. Such a process is undesirable, resulting in additional costs and time for users.
Therefore, a need exists for an electrical interconnect system having short probes and that prevents wiping action across the load board, obviates removal of the probes when replacing the bands, provides an upward force by the probes against the IC leads, achieves optimal alignment of the IC device within the socket, and has a manual nest that can be quickly and easily attached and detached from the contactor socket.